Vesicoureteric reflux and urinary tract infection in children

Evidence-based clinical practice guideline for management of urinary tract infection and primary vesicoureteric reflux

We present updated, evidence-based clinical practice guidelines from the Indian Society of Pediatric Nephrology (ISPN) for the management of urinary tract infection (UTI) and primary vesicoureteric reflux (VUR) in children. These guidelines conform to international standards; Institute of Medicine and AGREE checklists were used to ensure transparency, rigor, and thoroughness in the guideline development. In view of the robust methodology, these guidelines are applicable globally for the management of UTI and VUR. Seventeen recommendations and 18 clinical practice points have been formulated. Some of the key recommendations and practice points are as follows. Urine culture with > 104 colony forming units/mL is considered significant for the diagnosis of UTI in an infant if the clinical suspicion is strong. Urine leukocyte esterase and nitrite can be used as an alternative screening test to urine microscopy in a child with suspected UTI. Acute pyelonephritis can be treated with oral antibiotics in a non-toxic infant for 7-10 days. An acute-phase DMSA scan is not recommended in the evaluation of UTI. Micturating cystourethrography (MCU) is indicated in children with recurrent UTI, abnormal kidney ultrasound, and in patients below 2 years of age with non-E. coli UTI. Dimercaptosuccinic acid scan (DMSA scan) is indicated only in children with recurrent UTI and high-grade (3-5) VUR. Antibiotic prophylaxis is not indicated in children with a normal urinary tract after UTI. Prophylaxis is recommended to prevent UTI in children with bladder bowel dysfunction (BBD) and those with high-grade VUR. In children with VUR, prophylaxis should be stopped if the child is toilet trained, free of BBD, and has not had a UTI in the last 1 year. Surgical intervention in high-grade VUR can be considered for parental preference over antibiotic prophylaxis or in children developing recurrent breakthrough febrile UTIs on antibiotic prophylaxis.

Does preoperative screening VCUG affect the outcomes and complications of pyeloplasty in patients with ureteropelvic junction obstruction?

INTRODUCTION

The role of voiding cystourethrogram (VCUG) in evaluating vesicoureteral reflux (VUR) in patients with known ureteropelvic junction obstruction (UPJO) remains unclear. While VCUG is frequently performed, the incidence of concomitant VUR and UPJO is low, and VUR is often low-grade with high rates of spontaneous regression.

OBJECTIVE

To analyze the clinical relevance of VCUG in patients with UPJO by determining its incidence and studying the difference in clinical outcomes between patients with known, unknown, and negative VUR.

STUDY DESIGN

Retrospective review of patients with UPJO who underwent pyeloplasty from 2012 to 2020 with <18 years-old, unilateral UPJO, postoperative follow-up of ≥2 months and had at least 1 renal ultrasound (US) after pyeloplasty. Results were compared among 3 groups: patients who underwent VCUG before pyeloplasty and were found to have VUR (group 1), patients who underwent VCUG before pyeloplasty without VUR (group 2), and patients who did not have a VCUG before pyeloplasty (group 3).

RESULTS

A total of 275 patients met the inclusion criteria, of which 21 patients were classified in group 1, 166 patients in group 2, and 88 patients in group 3 (Table). The age at preoperative VCUG was 14.7 ± 32.9 months in group 1 and 15.17 ± 35.8 months in group 2 (p = 0.960). Overall, the incidence of concomitant UPJO and VUR was 11.2%. In group 1 the initial VUR grade was 5 in 2 patients, 4 in 3, 3 in 5, 2 in 7, and 1 in 4 patients. Of these, only 1 patient required ureteral reimplantation after pyeloplasty. Post-pyeloplasty, no significant differences were observed in complications (p = 0.7436), length of follow up (p = 0.3212), SFU grade 4 hydronephrosis (p = 0.2247), postoperative UTIs (p = 0.1047) and pyeloplasty success rate (p = 0.4206) among the 3 groups. Despite the use of antibiotic prophylaxis being significantly different amongst the three groups (p < 0.001), it was not associated with a lower incidence of postoperative UTIs (group 1 p = 0.068, group 2 p = 0.486, group 3 p = 1). In patients with reflux, an increase in age was associated with a decrease in the rates of complications (p = 0.019).

CONCLUSION

We found no significant difference in the outcomes in patients who had a preoperative VCUG as compared to those who did not. The preoperative diagnosis of VUR by VCUG changed the management in less than 1% of the study population and thus its role in patients with UPJO should be reevaluated.

Dual Challenge of a Cecoureterocele with Calculus: A rare case report

Ureteroceles are the most prevalent urinary tract malformations in humans. Only 5% of ureteroceles are predicted to prolapse and it usually occurs in childhood. We outline the clinical history, radiological results, and a potential course of treatment for this challenging condition. A 32-year-old female checked herself into our institution with complaints of burning urination and 20 years of complaints of urethral ballooning when urinating. Initial sonographic evaluation revealed that at the left vesicoureteric junction, a cystic lesion extends into the bladder, with a hyperechoic focus causing posterior acoustic shadowing. CT scan confirmed the diagnosis of an ureterocele with calculus. A voiding cystourethrogram revealed a left-sided ureterocele that descends down the urethra and into the interlabial region. CT cystogram verified the presence of a left-sided cecoureterocele with calculus. Cecoureterocele is a rare variant of ectopic ureteroceles. Girls experience this condition more frequently than boys, and they are predisposed to vesicoureteric reflux and recurrent infections. To prevent problems like renal function loss, recurrent urinary tract infections, and urinary incontinence, it is important to gain diagnostic confirmation of these circumstances. Less invasive surgical techniques like endoscopic ureterocele puncture or even nonoperative treatment appear to produce comparable functional outcomes. When a patient arrives with a urethral protrusion, one should be extra cautious. In this case report, a cecoureterocele that has prolapsed is presented in a rare way. It presents an important chance to evaluate the clinical and diagnostic characteristics of this urinary tract abnormality.

Endoscopic injection of bulking agents in pediatric vesicoureteral reflux: a narrative review of the literature

In the last 20 years, endoscopic injection (EI) has affirmed as a valid alternative to open surgery for management of pediatric vesicoureteral reflux (VUR). This study aimed to investigate and discuss some debated aspects such as indications, bulking agents and comparison, techniques of injection and comparison, predictive factors of success, use in specific situations. EI is minimally invasive, well accepted by patients and families, with short learning curve and low-morbidity profile. It provides reflux resolution rates approaching those of open reimplantation, ranging from 69 to 100%. Obviously, the success rate may be influenced by several factors. Recently, it is adopted as first-line therapy also in high grade reflux or complex anatomy such as duplex, bladder diverticula, ectopic ureters. The two most used materials for injection are Deflux and Vantris. The first is absorbable, easier to inject, has lower risk of obstruction, but can lose efficacy over time. The second is non-absorbable, more difficult to inject, has higher risk of obstruction, but it is potentially more durable. The two main techniques are STING and HIT. To date, the ideal material and technique of injection has not yet clearly established, but the choice remains dependent on surgeon's preference and experience.

Parental Knowledge and Awareness of Childhood Urinary Tract Infections: A Cross Sectional Survey

BACKGROUND

Parent's misconceptions or lack of knowledge about childhood urinary tract infections (UTIs) can negatively impact their children's health. Therefore, the present study aimed to determine the childhood urinary tract infections awareness and understanding among parents in Saudi Arabia.

PATIENTS AND METHODS

An online validated cross-sectional survey of parents in Saudi Arabia was conducted from August to September 2021. Study participants who met the inclusion criteria were selected using a convenience sampling technique. A questionnaire with two domains was used to assess parental awareness of childhood urinary tract infection symptoms, complications, treatment, prevention, epidemiology, and diagnosis. The total childhood urinary tract infections awareness scores were classified into three categories: low awareness, moderate awareness, and high awareness. Descriptive statistics were used to determine the data distribution. A chi-square test was used to evaluate the relationship between parental awareness about urinary tract infections in children and other variables. Statistical significance was established at 0.05.

RESULTS

Of the 1688 parents who completed the survey, 1289 (76.4%) were female, 1581 (93.7%) were married, and 1161 (68.8) had a university degree. Parent's total awareness scores were high; however, individual domain scores indicate a moderate level of knowledge. Statistically significant relationship were observed between total awareness and gender, occupation, and level of educational level ((P=0.004, P=0.001, P=0.007, respectively). Another statistically significant relationship was noted between the history of urinary tract infections and awareness of disease prevention (P=0.009).

CONCLUSION

In Saudi Arabia, parental knowledge about childhood urinary tract infections is moderate to high. However, future studies are needed to investigate gender, educational, and occupational variations in childhood UTI knowledge among parents in Saudi Arabia.

Extravesical vs. intravesical ureteric reimplantation for primary vesicoureteral reflux: A systematic review and meta-analysis

PURPOSE

This study aims to compare the outcomes of extravesical (EVUR) and intravesical (IVUR) ureteric reimplantation for primary vesicoureteral reflux (VUR) via systematic review and meta-analysis.

METHODS

Literature review from Medline, Embase, and Cochrane since inception to March 2022 was performed. Meta-analysis was conducted on eligible randomized controlled trials (RCT) and observational cohort studies (OCS) comparing outcomes between EVUR and IVUR.

RESULTS

Twelve studies were included, comprising 577 patients (778 ureters) operated by EVUR and 395 patients (635 ureters) by IVUR. Pre-operative VUR grade, postoperative VUR persistence and hydronephrosis was not statistically significant. EVUR had shorter operative time [mean differences (MD) -22.91 min; 95% confidence interval (CI), -44.53 to -1.30, P = 0.04] and hospital stay (MD -2.09 days; 95% CI, -2.82 to -1.36, P < 0.00001) compared to IVUR. Bilateral EVUR had higher risk of postoperative acute urinary retention (ARU) (8.1%) compared to bilateral IVUR (1.7%) (OR = 4.40; 95% CI, 1.33-14.58, P = 0.02). No patient undergoing unilateral EVUR or IVUR experienced ARU.

CONCLUSION

Both EVUR and IVUR are equally effective in correcting primary VUR. Operative time and hospital stay are shorter after EVUR compared to IVUR. However, bilateral EVUR is associated with higher risk of postoperative ARU.

Is there a relationship between renal scarring and neutrophil-to-lymphocyte ratio in patients with vesicoureteral reflux?

OBJECTIVES

Vesicoureteral reflux (VUR) exacerbates the risk of renal scarring by establishing a ground for pyelonephritis. It is known that the inflammatory process is more influential than the direct damage caused by bacterial infection in the development of renal scars after pyelonephritis. Therefore, the present study aims to investigate the relationship between renal scarring and systemic inflammatory markers in patients with VUR.

MATERIAL AND METHODS

Hundred and ninety-two patients (116 females, 76 males) diagnosed with VUR were divided into two groups based on the presence or absence of renal scarring and into three groups according to the grade of VUR (low, moderate and high). Neutrophil count, lymphocyte count, mean platelet volume (MPV) and neutrophil-to-lymphocyte ratio (NLR) were compared among the groups.

RESULTS

Of the 192 patients, 102 had renal scarring. The age and gender distribution did not differ significantly between the groups with and without renal scarring (p > 0.05). However, the grade of reflux and lymphocyte count were significantly higher in the group with renal scarring (p < 0.05), and the NLR was significantly lower in the group with renal scarring (p < 0.05). The lymphocyte count was significantly higher (p < 0.05) and NLR was significantly lower in the high-grade VUR group (p < 0.05). However, MPV values did not differ significantly (p > 0.05) between the groups.

CONCLUSIONS

NLR can be used to predict renal scarring in patients with VUR, especially in the period of 3-6 months after the first attack of infection, and may even serve as a candidate marker for treatment selection. However, larger series and prospective studies are needed.

Is endothelial glycocalyx damage a cause of renal scarring in vesicoureteral reflux with febrile urinary tract infection?

INTRODUCTION

Endothelial glycocalyx is a luminal layer which can be damaged by inflammatory agents or pathogens. The endothelial glycocalyx damage is thought to have a role in the formation of renal scars in children who have febrile urinary tract infection and vesicoureteral reflux. This study aimed to compare the blood levels of endothelial glycocalyx components heparan sulfate and Syndecan-1 in children with and without renal scarring due to vesicoureteral reflux-associated febrile urinary tract infection.

MATERIALS AND METHODS

Data of the patients diagnosed with vesicoureteral reflux without renal scarring (Group 1), patients with vesicoureteral reflux and renal scarring (Group 2), and completely healthy children (Group 3) were retrospectively reviewed. Blood levels of heparan sulfate and Syndecan-1 were measured and the results were compared.

RESULTS

The entire cohort consisted of 90 patients; there were 30 patients in each group. Mean patient age was 49.7±18.0 months. Mean serum heparan sulfate (42.90±18.90 ng/mL) and Syndecan-1 (37.59±13.77 ng/mL) levels of Group 2 were significantly higher than those of other groups. The cut-off value for heparan sulfate was 35.17 ng/mL, with a 63% sensitivity and 86% specificity. The cut-off value for Syndecan-1 was 29.99 ng/mL with a 70% sensitivity and 80% specificity.

CONCLUSION

Our findings indicate that blood levels of heparan sulfate and Syndecan-1 could be related with renal scarring in patients with vesicoureteral reflux, especially in the setting of febrile urinary tract infection. However, due to their low sensitivity, these biomarkers should be used along with clinical data.

Predictive score for vesicoureteral reflux in children with a first febrile urinary tract infection

OBJECTIVE

To develop a simple score for predicting vesicoureteral reflux after a first febrile urinary tract infection in children.

METHODS

A retrospective cohort study was conducted for a 12-year period (January 2008 to December 2019), including patients aged <72 months who underwent renal ultrasonography and voiding cystourethrography after a first febrile urinary tract infection. Patients with a history of antenatal hydronephrosis were excluded. The prediction model and score for vesicoureteral reflux were developed using multivariate logistic regression analysis.

RESULTS

Out of 260 patients in total (median age 4 months, 172 boys), 41 (16%) had vesicoureteral reflux. The score was based on four independent risk factors, including age >6 months (odds ratio 2.71, 95% confidence interval 1.27-5.76), presence of sepsis (odds ratio 3.44, 95% confidence interval 1.31-9.04), white blood cell count ≥15 000/mm³ (odds ratio 1.83, 95% confidence interval 0.88-3.8) and abnormal renal ultrasonography results (odds ratio 2.08, 95% confidence interval 1-4.31). A lower probability of vesicoureteral reflux (positive likelihood ratio = 0.66; P = 0.001) was found in the low-risk group (scores 0-2), whereas a higher probability of vesicoureteral reflux (positive likelihood ratio = 2.54; P = 0.001) was found in the high-risk group (scores 3-5). The predictive ability of the model was 70%.

CONCLUSIONS

The scores developed based on the patient characteristics and renal ultrasonography are useful in predicting presence of vesicoureteral reflux after a first febrile urinary tract infection in children and could guide clinicians' decisions to perform additional imaging studies.

Contrast-enhanced voiding urosonography for the diagnosis of vesicoureteral reflux and intrarenal reflux: a comparison of diagnostic performance with fluoroscopic voiding cystourethrography

Purpose

This study evaluated the diagnostic performance of contrast-enhanced voiding urosonography (ce-VUS) using a second-generation ultrasound contrast agent for the diagnosis of vesicoureteral reflux (VUR) and intrarenal reflux (IRR), and compared it with that of standard fluoroscopic voiding cystourethrography (VCUG).

Methods

Thirty-two consecutive children from April to October 2019 were included in this study. ce-VUS and VCUG were performed simultaneously by two operators with intravesical infusion of a mixture of ultrasound contrast medium, iodinated contrast medium and water. Two pediatric radiologists independently reviewed the ce-VUS and VCUG images and reported the presence and degree of VUR (grades I-V), and the presence and type of IRR.

Results

Twenty-seven of 63 urinary systems showed VUR. Interobserver agreement for VUR grading was very good for both examinations (κ=0.87; 95% confidence interval [CI], 0.82 to 0.92 for ce-VUS and κ=0.92; 95% CI, 0.87 to 0.96 for VCUG). The detection rate of VUR showed no significant difference between the two examinations (P=0.370). Four cases of VUR were missed on ce-VUS, while one case of VUR was missed on VCUG. All four false-negative cases on ce-VUS were grade 1 VUR. The two examinations showed very good agreement regarding VUR grading (κ =0.89; 95% CI, 0.81 to 0.96). IRR was more frequently detected with ce-VUS than with VCUG (10 cases with ce-VUS vs. 3 cases with VCUG, P=0.016).

Conclusion

ce-VUS showed very good agreement with VCUG for detecting grade 2 VUR and above, while grade 1 VUR was sometimes missed with ce-VUS. IRR was more frequently detected with ce-VUS than with VCUG.

Trends in the surgical management of vesicoureteral reflux in Finland in 2004-2014

OBJECTIVES

Previous data on the trends of surgical treatment of vesicoureteral reflux outside USA are scarce. The aim of this study was to clarify the national trends of operative treatment of vesicoureteral reflux (VUR) in Finland.

METHODS

We analyzed national data from Finnish Care Register for Health Care on children (<16 years of age) surgically treated for VUR in 2004-2014.

RESULTS

Endoscopic injections of the ureteral orifices were primarily performed for 1212 and open ureteral reimplantation for 272 children. The use of both types of surgery decreased during the study period (p = 0.0043 and p < 0.001, respectively). The median age at surgery for VUR was lower in those treated with open ureteral reimplantation than those with endoscopic injections of the ureteral orifices [3 and 4 years, respectively] (p = 0.0001). The length of hospital stay was significantly longer (median 9.9 days) with open ureteral reimplantation compared to that (median 1.3 days) with endoscopic injections (p < 0.0001) and did not change during the study period. Reoperations were significantly more common in patients who were primarily treated with endoscopic injections (n = 146/1072, 14%) than with ureteral reimplantation (n = 7/230, 3%) (p < 0.0001).

CONCLUSIONS

While the best treatment options for VUR remain debatable, operative treatment of VUR has become less common in Finland. HIGHLIGHTS Recent data on the trends of treatment of vesicoureteral reflux outside USA are scarce. Surgical treatment for vesicoureteral reflux decreased in Finland during the study period. The length of stay was longer but reoperations were needed less often with ureteral reimplantation compared to endoscopic injections.

Relationship between Vesicoureteral Reflux and Glomerular Filtration Rate in Children

Vesicoureteral reflux (VUR) is one of the most common urinary tract anomalies in children and causes renal damage and studies focusing on the effect of VUR on renal function are rare. We recruited 35 primary VUR patients with recurrent urinary tract infection (UTI) and 10 non-VUR patients with recurrent UTI. Contrast-enhanced voiding urosonography (ceVUS) was performed for VUR grading, and renal dynamic imaging was used for evaluating glomerular filtration rate (GFR, mL/min). Standardized GFR (sGFR), namely GFR/BSA (mL·min^-1·m^-2), was calculated based on the body surface area (BSA). Total sGFR (tsGFR, mL·min^-1·m^-2) was obtained from the sum of sGFR on the left and right sides of all the children. The risk of renal regurgitation was equal in the unilateral reflux group. The sGFR of children with grade IV (45.74±18.05 mL·min^-1·m^-2) and grade V (49.67±23.63 mL·min^-1·m^-2) reflux was significantly lower than that in children with grade III (77.69 ±22.21 mL·min^-1·m^-2). The renal function compensation of contralateral non-reflux kidney increased in unilateral reflux group, which was higher than that in the control group and level II, IV and V of reflux group respectively. In VUR group of the same grade, sGFR decreased with the age at diagnosis. In unilateral grade V reflux group, the tsGFR was lower than that in the unilateral grade III reflux group (133.51±48.21 vs. 186.87±53.49 mL·min^-1·m^-2). The patients with VUR of unilateral grade II were significantly older than those with VUR of unilateral grades III and IV. This study indicates that severe VUR is significantly associated with decreased renal function. Therefore, VUR should be diagnosed early and managed individually.

Urinary Tract Infection in Children

BACKGROUND

Urinary Tract Infection (UTI) is a common infection in children. Prompt diagnosis and appropriate treatment are very important to reduce the morbidity associated with this condition.

OBJECTIVE

To provide an update on the evaluation, diagnosis, and treatment of urinary tract infection in children.

METHODS

A PubMed search was completed in clinical queries using the key terms "urinary tract infection", "pyelonephritis" OR "cystitis". The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. The search was restricted to English literature and the pediatric age group. Patents were searched using the key terms "urinary tract infection" "pyelonephritis" OR "cystitis" from www.google.com/patents, http://espacenet.com, and www.freepatentsonline.com.

RESULTS

Escherichia coli accounts for 80 to 90% of UTI in children. The symptoms and signs are nonspecific throughout infancy. Unexplained fever is the most common symptom of UTI during the first two years of life. After the second year of life, symptoms and signs of pyelonephritis include fever, chills, rigor, flank pain, and costovertebral angle tenderness. Lower tract symptoms and signs include suprapubic pain, dysuria, urinary frequency, urgency, cloudy urine, malodorous urine, and suprapubic tenderness. A urinalysis and urine culture should be performed when UTI is suspected. In the work-up of children with UTI, physicians must judiciously utilize imaging studies to minimize exposure of children to radiation. While waiting for the culture results, prompt antibiotic therapy is indicated for symptomatic UTI based on clinical findings and positive urinalysis to eradicate the infection and improve clinical outcome. The choice of antibiotics should take into consideration local data on antibiotic resistance patterns. Recent patents related to the management of UTI are discussed.

CONCLUSION

Currently, a second or third generation cephalosporin and amoxicillin-clavulanate are drugs of choice in the treatment of acute uncomplicated UTI. Parenteral antibiotic therapy is recommended for infants ≤ 2 months and any child who is toxic-looking, hemodynamically unstable, immunocompromised, unable to tolerate oral medication, or not responding to oral medication. A combination of intravenous ampicillin and intravenous/intramuscular gentamycin or a third-generation cephalosporin can be used in those situations. Routine antimicrobial prophylaxis is rarely justified, but continuous antimicrobial prophylaxis should be considered for children with frequent febrile UTI.

The evaluation of vesicoureteral reflux among children using contrast-enhanced ultrasound: a literature review

INTRODUCTION

Voiding cystourethrogram (VCUG) with fluoroscopy remains the gold standard for detection and evaluation of vesicoureteral reflux (VUR) among children. However, the ionizing radiation exposure remains a concern for this diagnostic modality. Recent studies have proposed using contrast-enhanced ultrasound as an alternative option for VUR screening and follow-up in children. The aim of the study was to review the literature of comparative studies that assessed the diagnostic accuracy of contrast-enhanced ultrasound compared with VCUG.

METHODOLOGY

A systematic literature search was performed on electronic medical literature databases in July 2017. Literature identification, screening, and assessment of eligibility were performed by five reviewers with a pediatric radiologist. Literature was summarized for the study population, contrast used, and ultrasound mode as well as the timing of comparative reference study being performed. The studies were clustered according to the kind of contrast used. Reported diagnostic accuracy was extracted from individual studies and summarized across the included studies using descriptive statistics of median and interquartile range (IQR).

RESULT

A total of 45 comparative studies were identified as eligible for the summary of the literature. Two generations of ultrasound contrast were identified in the available studies (first generation, Levovist and second generation, SonoVue). For the ultrasound studies using the first-generation contrast, the median sensitivity, regardless of the ultrasound mode, was 90.25 (IQR 83.25-97), and the median specificity was 93 (IQR 91.3-95.25). Among studies using the second-generation contrast, the median sensitivity was 86.26 (IQR 81.13-97), and the median specificity was 90.99 (IQR 84-98). No serious adverse events were reported in any of the studies.

CONCLUSION

Overall, this review highlights the application of contrast-enhanced ultrasound for its advantage of no exposure to ionizing radiation and diagnostic accuracy relatively comparable to VCUG in the evaluation of VUR. In addition to the functional evaluation of the VUR, it also provides an anatomic evaluation of the kidneys and bladder with ultrasound imaging. However, one should also note that this alternate procedure is highly operator dependent where diagnostic accuracy is excellent when the expertise is available.

Delayed diagnosis of primary vesicoureteral reflux in children with recurrent urinary tract infections: Diagnostic approach and renal outcomes

OBJECTIVE

In this study, we aimed to assess renal outcomes of delayed diagnosis of dilating primary vesicoureteral reflux (VUR) following recurrent febrile urinary tract infections (fUTIs) and its diagnostic imaging procedures.

MATERIAL AND METHODS

The medical records of patients who underwent ultrasonography (US), non- acute dimercaptosuccinic acid (Tc-99mDMSA) scintigraphy and voiding cystourethrography (VCUG), and who were older than 2 years at the time of VUR diagnosis were retrospectively reviewed.

RESULTS

A total of 32 children (female, n=27: 84.4%) with a mean age of 7.67±3.34 years at the time of diagnosis of VUR were included in the study. Grade III, IV, V VUR were found in 22%, 69%, and 9% of the patients, respectively. At the time of VUR diagnosis, abnormal US findings were detected in 75% of the cases. Tc-99mDMSA detected abnormalities in 83.9% (7 with a single scar, 7 with multiple lesions, 12 with reduced kidney function) of the patients. Estimated glomerular filtration rate of 3 patients with bilateral grade IV VUR was <75 mL/min/1.73 m². In 5 patients (16%), VUR could not be predicted by US+DMSA scintigraphy (Grade IV VUR in 3 and Grade III in 2 cases ). The sensitivity in predicting VUR was 75.00% (95% CI: 56.60-88.54) and 83.87% (95% CI: 66.27-94.55), respectively, for US alone and combined US+DMSA.

CONCLUSION

VCUG should be performed routinely in addition to US and non-acute DMSA in all children referred with recurrent fUTIs. Awareness of childhood UTI in public and healthcare personnels should be increased in order to refer these patients at a early stage to pediatric urology and nephrology units.

Nuclear Medicine in Pediatric Nephro-Urology: An Overview

In the context of ante-natally diagnosed hydronephrosis, the vast majority of children with a dilated renal pelvis do not need any surgical treatment, as the dilatation resolves spontaneously with time. Slow drainage demonstrated at Tc-99m-mercaptoacetyltriglycine (MAG3) renography does not necessarily mean obstruction. Obstruction is defined as resistance to urinary outflow with urinary stasis at the level of the pelvic-ureteric junction (PUJ) which, if left untreated, will damage the kidney. Unfortunately this definition is retrospective and not clinically helpful. Therefore, the identification of the kidney at risk of losing function in an asymptomatic patient is a major research goal. In the context of renovascular hypertension a DMSA scan can be useful before and after revascularisation procedures (angioplasty or surgery) to assess for gain in kidney function. Renal calculi are increasingly frequent in children. Whilst the vast majority of patients with renal stones do not need functional imaging, DMSA scans with SPECT and a low dose limited CT can be very helpful in the case of complex renal calculi. Congenital renal anomalies such as duplex kidneys, horseshoe kidneys, crossed-fused kidneys and multi-cystic dysplastic kidneys greatly benefit from functional imaging to identify regional parenchymal function, thus directing further management. Positron emission tomography (PET) is being actively tested in genito-urinary malignancies. Encouraging initial reports suggest that F-18-fluorodeoxyglucose (FDG) PET is more sensitive than CT in the assessment of lymph nodal metastases in patients with genito-urinary sarcomas; an increased sensitivity in comparison to isotope bone scans for skeletal metastatic disease has also been reported. Further evaluation is necessary, especially with the promising advent of PET/MRI scanners. Nuclear Medicine in paediatric nephro-urology has stood the test of time and is opening up to new exciting developments.

Evaluation and management of recurrent urinary tract infections in children: state of the art

Urinary tract infections (UTIs) represent an important cause of febrile illness in young children and can lead to renal scarring and kidney failure. However, diagnosis and treatment of recurrent UTI in children is an area of some controversy. Guidelines from the American Academy of Pediatrics, National Institute for Health and Clinical Excellence and European Society of Paediatric Radiology differ from each other in terms of the diagnostic algorithm to be followed. Treatment of vesicoureteral reflux and antibiotic prophylaxis for prevention of recurrent UTI are also areas of considerable debate. In this review, we collate and appraise recently published literature in order to formulate evidence-based guidance for the diagnosis and treatment of recurrent UTI in children.

The value of direct radionuclide cystography in the detection of vesicoureteral reflux in children with normal voiding cystourethrography

BACKGROUND

Vesicoureteral reflux (VUR) is one of the most important risk factors for urinary tract infection (UTI). Diagnosis and treatment of VUR is important to prevent irreversible complications, such as renal scarring and chronic renal failure. This study was conducted to assess the value of direct radionuclide cystography (DRNC) in the detection of VUR in children with UTI and a normal voiding cystourethrography (VCUG).

METHODS

DRNC was performed in 35 children with a normal VCUG after an episode of febrile UTI who had hydronephrosis or hydroureter, abnormal acute dimercaptosuccinic acid (DMSA) scan results and/or febrile UTI recurrence. This study was conducted in the nephrology department of Mofid Children's Hospital, Tehran (Iran).

RESULTS

The results were statistically analyzed. Among the 70 ureters studied, 33 (49.1 %) were observed to have VUR. Of these, 17 (51.5 %) had mild, 14 (42.4 %) moderate, and 2 (6.1 %) severe reflux. A significant relationship was observed between DRNC results and DMSA renal scan findings (P < 0.05).

CONCLUSIONS

Based on our results, we suggest that DRNC may reveal VUR despite a normal VCUG in children with hydronephrosis, abnormal acute DMSA, and/or recurrent febrile UTI.

Gender-based differences in pediatric nuclear medicine

Gender-based differences commonly encountered in pediatric nuclear medicine reflect both basic embryologic differences of the sexes, which are evident from infancy, and evolving physiological changes due to gender, which occur as the pediatric patient grows, undergoes puberty, and matures to adulthood. It is important for a nuclear medicine physician or radiologist to know both the gender and the age of a patient when interpreting her or his studies. It is also important that the reading physician be familiar with the normally evolving physiological changes that are specific for that patient's stage of development. It is particularly important that the reading physician consider such changes when comparing serial studies of the patient that are acquired during the patient's transitions through her or his different significant stages of development. Many pediatric nuclear medicine imaging protocols are modifications or adaptations of the protocols for adult imaging. Physicians reading pediatric studies must routinely incorporate knowledge on age and gender that is relevant to the patient for any given study. The age-defined gender-based subtleties of potential findings in pediatric nuclear medicine studies are often underrecognized. However, they are often of interest and at times important in the workup of both benign entities and pathologic processes of the pediatric patient.

Efficacy of a cartoon and photograph montage storybook in preparing children for voiding cystourethrogram

BACKGROUND

Undergoing voiding cystourethrogram (VCUG) can be distressing for children.

OBJECTIVE

To assess the efficacy of a cartoon and photograph montage storybook in preparing children for VCUG.

MATERIALS AND METHODS

Outpatient children (ages 2-14 years) who had VCUGs between December 2011 and June 2012 were randomly assigned to two groups; one group received the storybook a week before the procedure. Parents and guardians were asked to complete an anonymous survey rating their child's tolerance of the exam from 1 to 5, worst to best, immediately after VCUG. The VCUG technologist also rated the child's tolerance.

RESULTS

Children prepared for VCUG with the storybook had less distress than those without. Results were analyzed by Cochran-Mantel-Haenszel and Cochran-Armitage Trend exact tests, a P value of both tests of 0.0092 indicating a statistically significant difference between the tolerance scores of children prepared with the storybook and those without. Effects of gender and history of VCUG were not statistically significant. Two-thirds of all children had no other source of information.

CONCLUSION

The cartoon and photograph montage storybook format of preparing children for VCUG was effective in increasing their tolerance for the procedure. The storybook should be mailed out in advance because the majority of families did not pursue information on preparing their children for VCUG.

[Primary vesicoureteral reflux]

The never ending discussion about the diagnostics and treatment of vesicoureteral reflux (VUR) now includes arguments for diagnostic nihilism as well as invasive diagnostics and therapy, which is reminiscent of the debate on prostate cancer in adulthood. The common goal of all currently competing diagnostic strategies and approaches is the prevention of renal scars by the most effective and least burdensome approach. There is a difference between acquired pyelonephritic scars with VUR (acquired reflux nephropathy) and congenital reflux nephropathy (primary dysplasia) which cannot be influenced by any therapy.The VUR can be verified by conventional radiological voiding cystourethrography (VCUG), by urosonography, radionuclide cystography or even by magnetic resonance imaging (MRI). The guidelines of the European Association of Urology/European Society for Paediatric Urology (EAU/ESPU) recommend radiological screening for VUR after the first febrile urinary tract infection. Significant risk factors in patients with VUR are recurrent urinary tract infections (UTI) and parenchymal scarring and the patients should undergo patient and risk-adapted therapy. Infants with dilating reflux have a higher risk of renal scarring than those without dilatation of the renal pelvis. Bladder dysfunction or dysfunctional elimination syndrome represents a well-known but previously neglected risk factor in combination with VUR and should be treated prior to any surgical intervention as far as is possible.Certainly not every patient with VUR needs therapy. The current treatment strategies take into account age and gender, the presence of dysplastic or pyelonephritic renal scars, the clinical symptoms, bladder dysfunction and frequency and severity of recurrent UTI as criteria for the therapy decision. The use of an antibacterial prophylaxis as well as the duration is controversially discussed. Endoscopic therapy can be a good alternative to antibacterial prophylaxis or a surveillance strategy in patients with low grade VUR. In patients with dilating VUR and given indications for surgery, endoscopic treatment can be offered. However, parents should be completely informed about the significantly lower success rate of endoscopic therapy compared to open surgical procedures. The open surgical techniques guarantee the highest success rates and should be used in patients with a dilating VUR and high risk of renal damage.

Polydimethylsiloxane (macroplastique®) injection for vesicoureteral reflux in duplex ureters: a comparison with single renal systems

OBJECTIVE

VUR in patients with a duplex system (DS) is often treated by open surgery. The aim of this study was to evaluate the efficacy of subureteric polydimethylsiloxane (Macroplastique(®)) injection (SMING) in the management of VUR in duplex and single (SS) renal systems.

PATIENTS AND METHODS

Fifteen children (24 refluxing renal units) with VUR in DS underwent SMING. VUR was more frequent in the lower moiety. VUR was graded moderate/severe in 88% of renal units. There was a history of urinary tract infections in 40% of cases. The outcome for DS patients was compared with 44 children (60 refluxing renal units) with moderate/severe VUR in SS.

RESULTS

The VUR resolution/improvement rate was 88% in DS and 95% in SS patients. Ureteric reimplantation was required because of recurrent VUR in 13% and 7% of DS and SS groups, respectively. Transient ureteral obstruction was observed in 1/15 and 5/44 patients. Two required double-J ureteric stenting for 3 months.

CONCLUSION

SMING seems an effective treatment for VUR in both DS and SS patients, even in severe cases. The complication rate does not significantly differ between the two groups.

Plasma soluble urokinase plasminogen activator receptor in children with urinary tract infection

Objective:

In this prospective study we investigated the role of plasma levels of soluble urokinase plasminogen activator receptor (suPAR) in children with urinary tract infection.

Material and methods:

We measured the levels of plasma suPAR during admission in 42 children with suspected acute pyelonephritis and compared the results to acute DMSA scintigraphy.

Results:

The mean level of plasma suPAR at admission was significantly elevated in children with renal involvement (7.3 ng/ml) assessed by the DMSA scintigraphy compared to children without renal involvement (4.4 ng/ml, P = 0.010). The positive predictive value of suPAR seems high, since all patients without renal involvement had low suPAR values. During treatment the mean level of plasma suPAR decreased.

Conclusion:

We conclude that plasma suPAR could be of clinical use for the diagnosis of acute pyelonephritis and that high levels of plasma suPAR might reflect the level of renal involvement and could therefore be a new indicator for renal scarring.

Vesicoureteral reflux: current concepts and management implications

Long term controlled studies in children with vesicoureteral reflux (VUR) largely conducted in developed societies, challenge the validity of established management principles.The backflow of urine into the upper tracts is not a disease by itself, but part of a clinical spectrum which is heterogeneous and has low risk and high risk categories. Management, medical, endoscopic or surgical have to take into consideration the risk to the child not only from the reflux but also from renal dysplasia and voiding dysfunction which are important risk factors for end stage renal disease (ESRD) and perpetuation of VUR respectively. Social factors, parental choices and access to medical treatment are also important in choosing therapy.

Extravesical seromuscular ureteroneocystostomy: an effective and simple operation for treatment of vesicoureteral reflux

PURPOSE

To evaluate the success rate of extravesical seromuscular ureteroneocystostomy in the treatment of children with vesicoureteral reflux (VUR).

PATIENTS AND METHODS

In a prospective study from August 2005 to January of 2006, 15 patients (11 girls, 4 boys), median age of 9.5 years (range: 1-24 years), with high-grade VUR underwent operation. Urinary tract ultrasonography and voiding cystoureterography (VCUG) were the main diagnostic tools to detect VUR before the operation and at 3 months after the operation.

RESULTS

No VUR was detected at evaluation of 3-month postoperative VCUGs (14 cases, 93%). However, one child (7%) still had persistent VUR. This patient underwent reoperation and the length of the seromuscular tunnel was increased more with a favorable result. The overall success rate of this technique was about 93%.

CONCLUSION

Extravesical seromuscular ureteroneocystostomy is simple and effective method for the treatment of VUR in children.

Therapy Insight: what nephrologists need to know about primary vesicoureteral reflux

Vesicoureteral reflux (VUR) is the abnormal, retrograde flow of urine from the bladder to the upper urinary tract. This disease affects about 1% of otherwise normal children, 30-50% of those who present with urinary tract infections, and approximately 10% with prenatally diagnosed hydronephrosis. Over the past 50 years, tremendous progress has been made in the diagnosis, treatment and management of VUR. The realization that VUR is probably a component of generalized dysfunction of the lower urinary tract (i.e. dysfunctional elimination syndrome) has further enhanced understanding of the disease. This Review covers basic pathogenesis, diagnosis, management, clinical presentation, and current controversies surrounding VUR.

Postnatal management of isolated mild pelvic dilatation detected in antenatal period

AIM

Mild antenatal renal pelvic dilatation (ARPD) revealed by prenatal ultrasound (US) raises the question whether or not screening for vesicoureteral reflux (VUR) is mandatory. The aim of our study was to suggest guidelines for postnatal management of infants with mild ARPD defined as an antero-posterior (AP) dilatation >5 and <10 mm.

METHOD

Therefore we assessed the value of postnatal US at day 30 to predict VUR, the incidence of VUR at day 30 and the rate of spontaneous resolution at 1 year. Two hundred (200) infants with ARPD were included and had renal US and voiding cystourethrography (VCUG) at day 30. If VUR was present, VCUG was repeated 1 year later.

RESULTS

Incidence of VUR was 10% (20/200) at day 30 after birth and only 3% (6/200) 1 year later. VUR at day 30 was twice as frequent in children with postnatal dilatation (11%) than in nondilated kidneys (6%).

CONCLUSIONS

Considering the low incidence of VUR at 1 year, screening for VUR in mild ARDP seems not to be justified. However follow-up by US to detect increase in dilatation and clinical monitoring for signs of urinary infection is required.

Risk of hypertension in primary vesicoureteral reflux

The aim of this report was to estimate the risk of hypertension in children with primary vesicoureteral reflux (VUR). Between 1970 and 2004, 735 patients were diagnosed with VUR at a single tertiary renal unit. Of 735 patients, 664 (90%) were systematically followed and had multiple measurements of blood pressure. Hypertension was defined as values persistently above 95th for age, sex, and height in three consecutive visits. Risk of hypertension was analyzed by the Kaplan-Meier method. Of 664 patients followed, 20 (3%) developed hypertension. The estimated probability of hypertension was 2% (95%CI, 0.5%-3%), 6% (95%CI, 2%-10%), 15% (95%CI, 11%-20%) at 10, 15, and 21 years of age, respectively. The prevalence of hypertension has increased with age: it was 1.7% for patients with 1 yr-9.9 yr, 1.8% for adolescents with 10 yr-14.9 yr, 4.7% for patients with 15-19.9 yr, and 35% for patients>20 years at the end of the follow-up (P<0.001). It was estimated by survival analysis that 50% of patients with unilateral and bilateral renal damage would have sustained hypertension at about 30 and 22 years of age, respectively. Hypertension increased with age and was strongly associated with renal damage at entry in an unselected population of primary VUR.